[Qemu-devel] AccelClass initialization order question

[Qemu-devel] AccelClass initialization order question

[Chuck Tuffli]

While debugging an issue, I ran across something in the initialization
sequence of hardware accelerators. Being a noobie qemu developer, it's
hard to tell if I simply don't understand how AccelClass works or if
this is a bug.

The init_machine function for hardware accelerators is passed a
MachineState pointer via configure_accelerator(), but several elements
of the structure (e.g. ram_size, maxram_size, etc.) are not
initialized until well after this call. Should hardware accelerator
modules not look at MachineState and instead grab the global versions
of variables like ram_size? TIA.

--chuck

Re: [Qemu-devel] AccelClass initialization order question

[Stefan Hajnoczi]

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On Thu, Apr 20, 2017 at 08:18:51PM -0700, Chuck Tuffli wrote:
> While debugging an issue, I ran across something in the initialization
> sequence of hardware accelerators. Being a noobie qemu developer, it's
> hard to tell if I simply don't understand how AccelClass works or if
> this is a bug.
> 
> The init_machine function for hardware accelerators is passed a
> MachineState pointer via configure_accelerator(), but several elements
> of the structure (e.g. ram_size, maxram_size, etc.) are not
> initialized until well after this call. Should hardware accelerator
> modules not look at MachineState and instead grab the global versions
> of variables like ram_size? TIA.

Machine init isn't finished when configure_accelerator() is executed.
Perhaps existing accelerators just don't need these variables at
configure_accelerator() time.

What exactly are you trying to do?

Stefan

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